Hello, welcome to healthcare magic. I understand from your query that you are having a boil in your underarm area. It is medically called as furuncle. You need to take a course of oral antibiotic like cephalexin or amoxycillin. These need to be prescribed by your dermatologist/ GP. You could also apply a cream containing 1 % fusidic acid or 2 % mupirocin twice a day for 10 days. Hot packs can be used. They will provide symptomatic relief and may also aid draining of the pus. Keep the area clean and dry. Do not do reverse shaving as this will promote ingrowing of hairs which can become infected to form boils. Always shave in the direction of hair growth. Hope this helps you. Take care.